My thinking was long bob's lines of thinking. They changed for a reason. I'm not going to run out and buy new tubes ASAP, but will keep on eye on it (and others build/test threads). The OEM system wasn't designed to push water 10 feet forward and then 10 feet back with lots of extra bends. Just something to be aware of and keep tabs on and make a decision later. For all we know their supplier said "hey, we can supply these tubes for less $".